1. Field of the Invention
The present invention relates to a method and device for the generation of printed images which define patterns to be used in graphic information exhibiting panels of the type made up of a plurality of cylinder, converging lenses arranged parallel each other.
2. Description of the Related Art
A number of arrangements is known for the exhibition of printed images reaching different optic effects. Some of these arrangements resort to a plate formed by a plurality of cylinder, parallel lenses defining a focal plane.
A family of these optic arrangements consists in devices allowing the exhibition of two or more different graphic images, one at a time, depending on the angle formed by the sight with the focal plane of the device. This kind of devices demands that the observer focuses his eyes at the real distance which separates him from the exhibitor. Depending on the structure of the graphic pattern laid out behind the plate of lenses, different effects may be presented.
If the two images to be exhibited are lightly different each other, by an angular displacement of the same scene, a tridimensional effect is visualized.
If on the contrary, the difference between an image and the other one corresponds to that which would be produced due to a virtual variation of time, then an animation effect is visualized. But this animation effect is actually reached through the visualization of very few frames (two through eight) due to the technique of composing the graphic pattern to be installed behind the lenticular plate.
Basically the structure of the graphic pattern of these devices consists in a screen formed by a plurality of lines having only a longitudinal resolution (parallel to the axis of the cylinder lenses), and arranged in such a way that the consecutive lines belong to consecutive images and two lines are separated in the same image by the same distance they occupied in the original image. Another characteristic of these graphic patterns is that below each cylinder lens, there shall be a complete set of lines belonging to all images to be visualized. All of this limits the number of different images that may be exhibited, and due to the accuracy with which the lines of the graphic pattern must be aligned with respect to the cylinder lenses, up to now the reduction of the number of images to be exhibited has been preferred, as well as the increase of the width of lines in order to absorb the alignment error.
Another family of optic arrangements using cylinder, converging, parallel multilenticular plates consists in devices allowing the exhibition of graphic images, which seem to follow the observer when the latter has a relative movement which is cross-sectional to the optic axis of the lenses. Depending on the structure of the graphic pattern installed behind the multilenticular plate, whether static or animated effects may be presented, which, in both cases, present before the observer notwithstanding that the latter has a relative movement with respect to the device.
The graphic patterns of this second family of exhibiting devices, unlike the first one, are formed by a plurality of strips which are parallel to the lenses. These strips have graphic information, both longitudinal and cross-sectional, and the observer must focus his sight on the infinity, which occurs automatically, that is to say, without the observer having to do any conscious handling in focusing.
In both families of devices, the possible animation effect is produced by the relative movement of the observer with respect to the device. In this respect, the exhibiting devices are passive, since different observers having different movements with respect to the exhibitor, observe different optic effects.
An important technical problem arising from both families of exhibiting devices is related to the techniques used to form the graphic patterns from the images it is desired to show. These techniques should try to be efficient both in the geometrical accuracy of the graphic pattern to be obtained, and in the speed and production costs of said graphic patterns.
We do not know more or less automatic techniques to handle the images in order to mix them as required to form the graphic patterns already mentioned.